<div class="panel panel-primary">
  <div class="panel-heading">*ngIf的用法</div>
  <div class="panel-body">
    <p *ngIf="isShow" style="background-color:crimson">显示还是不显示</p>
    <button class="btn btn-success" (click)="toggleshow()">控制显示隐藏</button>
  </div>
</div>
